organic compounds
4-[2-(4-Bromophenyl)hydrazinylidene]-3-methyl-5-oxo-4,5-dihydro-1H-pyrazole-1-carbothioamide
aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri, Mangalore 574 199, India
*Correspondence e-mail: hkfun@usm.my
In the title compound, C11H10BrN5OS, the approximately planar pyrazole ring [maximum deviation = 0.014 (2) Å] forms a dihedral angle of 5.49 (13)° with the benzene ring. An intramolecular N—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, molecules are linked through intermolecular N—H⋯S and N—H⋯O hydrogen bonds, forming a two-dimensional network parallel to (100). A short Br⋯Br contact of 3.5114 (6) Å is also observed.
Related literature
For details and applications of pyrazole compounds, see: Isloor et al. (2009); Rai et al. (2008) Bradbury & Pucci (2008); Girisha et al. (2010). For standard bond-length data, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995).
Experimental
Crystal data
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Refinement
|
Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL and PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL and PLATON.
Supporting information
https://doi.org/10.1107/S1600536811034726/lh5323sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811034726/lh5323Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S1600536811034726/lh5323Isup3.cml
To a solution of ethyl-2-[(4-bromophenyl)hydrazono]-3-oxobutanoate (0.01 mol) dissolved in glacial acetic acid (20 ml), a solution of thiosemicarbazide (0.02 mol) in glacial acetic acid (25 ml) was added and the mixture was refluxed for 4 h. This was cooled and allowed to stand overnight. The solid product which separated out was filtered and dried. It was then recrystallized from ethanol. Crystals suitable for X-ray analysis were obtained by slow evaporation of a solution of (I) in a 1:2 mixture of DMF and ethanol.
Atoms H1N4, H1N5 and H2N5 were located in difference Fourier maps and refined freely [N–H = 0.81 (4)–0.82 (3) Å]. The remaining H atoms were positioned geometrically [C–H = 0.93 or 0.96 Å] and were refined using a riding model, with Uiso(H) = 1.2 or 1.5 Ueq(C). A rotating group model was applied to the methyl groups.
The pyrazole ring is a prominent structural moiety found in numerous pharmaceutically active compounds. This is mainly due to the easy preparation and the important pharmacological activity. Therefore, the synthesis and selective functionalization of pyrazoles have been the focus of active research area over the years (Isloor et al., 2009). Pyrazoles have been reported to possess antibacterial activity (Rai et al., 2008), and inhibitor activity against DNA gyrase and topoisomerase IV at their respective ATP-binding sites (Bradbury & Pucci, 2008). Moreover, pyrazole-containing compounds have received considerable attention owing to their diverse chemotherapeutic potentials including versatile anti-inflammatory and antimicrobial activities (Girisha et al., 2010). The synthetic route followed for obtaining the title compound involves the diazotization of substituted anilines to give the
followed by coupling with ethyl acetoacetate in the presence of sodium acetate to give the corresponding oxobutanoate which on further reaction with thiosemicarbazide in acetic acid gave the required thioamides.The
of the title compound (I) is shown in Fig. 1. The pyrazole (N1,N2/C1–C3) ring is approximately planar, with a maximum deviation of 0.014 (2) Å for atom N1. The dihedral angle between the benzene (C4–C9) ring and the pyrazole (N1,N2/C1–C3) ring is 5.49 (13)°. An intramolecular N4—H1N4···O1 hydrogen bond generates an S(6) ring motif (Bernstein et al., 1995). The bond lengths (Allen et al., 1987) and angles are within normal ranges.In the
(Fig. 2) molecules are linked through intermolecular N5—H1N5···S1i and N5—H2N5···O1ii hydrogen bonds (Table 1) forming a two-dimensional network parallel to (1 0 0). A short Br···Br contact of 3.5114 (6) Å is also observed.For details and applications of pyrazole compounds, see: Isloor et al. (2009); Rai et al. (2008) Bradbury & Pucci (2008); Girisha et al. (2010). For standard bond-length data, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995).
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).C11H10BrN5OS | F(000) = 1360 |
Mr = 340.21 | Dx = 1.686 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 4204 reflections |
a = 25.6080 (18) Å | θ = 2.9–27.8° |
b = 11.6686 (8) Å | µ = 3.22 mm−1 |
c = 9.0823 (6) Å | T = 296 K |
β = 98.907 (2)° | Slab, orange |
V = 2681.2 (3) Å3 | 0.48 × 0.33 × 0.17 mm |
Z = 8 |
Bruker APEXII DUO CCD area-detector diffractometer | 3869 independent reflections |
Radiation source: fine-focus sealed tube | 2776 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.034 |
φ and ω scans | θmax = 30.0°, θmin = 2.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −36→36 |
Tmin = 0.306, Tmax = 0.609 | k = −16→14 |
15576 measured reflections | l = −12→12 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.040 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.127 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0646P)2 + 2.3027P] where P = (Fo2 + 2Fc2)/3 |
3869 reflections | (Δ/σ)max = 0.001 |
185 parameters | Δρmax = 0.46 e Å−3 |
0 restraints | Δρmin = −0.75 e Å−3 |
C11H10BrN5OS | V = 2681.2 (3) Å3 |
Mr = 340.21 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 25.6080 (18) Å | µ = 3.22 mm−1 |
b = 11.6686 (8) Å | T = 296 K |
c = 9.0823 (6) Å | 0.48 × 0.33 × 0.17 mm |
β = 98.907 (2)° |
Bruker APEXII DUO CCD area-detector diffractometer | 3869 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 2776 reflections with I > 2σ(I) |
Tmin = 0.306, Tmax = 0.609 | Rint = 0.034 |
15576 measured reflections |
R[F2 > 2σ(F2)] = 0.040 | 0 restraints |
wR(F2) = 0.127 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.46 e Å−3 |
3869 reflections | Δρmin = −0.75 e Å−3 |
185 parameters |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
S1 | 0.24780 (3) | 0.67093 (6) | 0.16175 (6) | 0.04971 (18) | |
Br1 | 0.476115 (14) | 1.36166 (3) | 0.95277 (4) | 0.07714 (17) | |
O1 | 0.29888 (8) | 0.85438 (14) | 0.39141 (19) | 0.0476 (4) | |
N1 | 0.30362 (8) | 0.65467 (16) | 0.43648 (19) | 0.0377 (4) | |
N2 | 0.32861 (9) | 0.58425 (17) | 0.5541 (2) | 0.0442 (5) | |
N3 | 0.37576 (9) | 0.85410 (17) | 0.6771 (2) | 0.0433 (4) | |
N4 | 0.36660 (9) | 0.95754 (18) | 0.6236 (2) | 0.0432 (4) | |
N5 | 0.26122 (10) | 0.4932 (2) | 0.3443 (2) | 0.0483 (5) | |
C1 | 0.35129 (9) | 0.7684 (2) | 0.6042 (2) | 0.0399 (5) | |
C2 | 0.31496 (9) | 0.77032 (19) | 0.4632 (2) | 0.0358 (4) | |
C3 | 0.35624 (11) | 0.6506 (2) | 0.6496 (3) | 0.0464 (6) | |
C4 | 0.39352 (9) | 1.0510 (2) | 0.6975 (2) | 0.0398 (5) | |
C5 | 0.43053 (11) | 1.0338 (2) | 0.8242 (3) | 0.0536 (6) | |
H5A | 0.4388 | 0.9600 | 0.8588 | 0.064* | |
C6 | 0.45488 (11) | 1.1273 (3) | 0.8982 (3) | 0.0581 (7) | |
H6A | 0.4794 | 1.1169 | 0.9840 | 0.070* | |
C7 | 0.44277 (10) | 1.2359 (2) | 0.8449 (3) | 0.0500 (6) | |
C8 | 0.40611 (11) | 1.2539 (2) | 0.7174 (3) | 0.0517 (6) | |
H8A | 0.3983 | 1.3276 | 0.6818 | 0.062* | |
C9 | 0.38156 (11) | 1.1601 (2) | 0.6447 (3) | 0.0498 (6) | |
H9A | 0.3568 | 1.1705 | 0.5595 | 0.060* | |
C10 | 0.27077 (9) | 0.6012 (2) | 0.3187 (2) | 0.0373 (5) | |
C11 | 0.38809 (16) | 0.6072 (3) | 0.7892 (4) | 0.0753 (10) | |
H11A | 0.3828 | 0.5261 | 0.7969 | 0.113* | |
H11B | 0.3772 | 0.6450 | 0.8733 | 0.113* | |
H11C | 0.4248 | 0.6224 | 0.7875 | 0.113* | |
H1N4 | 0.3475 (14) | 0.980 (3) | 0.548 (4) | 0.064 (9)* | |
H1N5 | 0.2727 (15) | 0.468 (3) | 0.425 (4) | 0.077 (11)* | |
H2N5 | 0.2458 (13) | 0.456 (3) | 0.275 (4) | 0.057 (9)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0660 (4) | 0.0450 (4) | 0.0326 (3) | 0.0018 (3) | −0.0098 (2) | 0.0007 (2) |
Br1 | 0.0707 (2) | 0.0514 (2) | 0.0982 (3) | −0.00776 (14) | −0.02193 (18) | −0.02813 (16) |
O1 | 0.0595 (11) | 0.0342 (9) | 0.0437 (9) | 0.0036 (7) | −0.0085 (8) | 0.0020 (6) |
N1 | 0.0453 (10) | 0.0322 (10) | 0.0316 (8) | −0.0025 (7) | −0.0064 (7) | 0.0006 (6) |
N2 | 0.0550 (12) | 0.0331 (10) | 0.0387 (9) | −0.0027 (9) | −0.0111 (8) | 0.0047 (7) |
N3 | 0.0467 (11) | 0.0381 (11) | 0.0420 (10) | −0.0061 (8) | −0.0032 (8) | −0.0022 (7) |
N4 | 0.0470 (11) | 0.0362 (11) | 0.0422 (10) | −0.0034 (8) | −0.0064 (8) | −0.0040 (8) |
N5 | 0.0642 (14) | 0.0411 (12) | 0.0341 (9) | −0.0113 (10) | −0.0092 (9) | −0.0014 (8) |
C1 | 0.0442 (12) | 0.0366 (12) | 0.0350 (9) | −0.0020 (9) | −0.0055 (8) | −0.0002 (8) |
C2 | 0.0408 (11) | 0.0326 (11) | 0.0327 (9) | 0.0001 (9) | 0.0018 (8) | −0.0002 (8) |
C3 | 0.0529 (14) | 0.0399 (13) | 0.0406 (11) | −0.0057 (10) | −0.0112 (10) | 0.0037 (9) |
C4 | 0.0388 (11) | 0.0379 (12) | 0.0411 (10) | −0.0039 (9) | 0.0012 (9) | −0.0064 (9) |
C5 | 0.0528 (15) | 0.0406 (14) | 0.0599 (14) | 0.0007 (11) | −0.0151 (11) | −0.0046 (11) |
C6 | 0.0519 (15) | 0.0527 (17) | 0.0606 (15) | 0.0019 (12) | −0.0203 (12) | −0.0123 (12) |
C7 | 0.0441 (13) | 0.0413 (14) | 0.0609 (14) | −0.0045 (10) | −0.0036 (10) | −0.0158 (11) |
C8 | 0.0554 (15) | 0.0351 (13) | 0.0600 (14) | −0.0030 (11) | −0.0053 (11) | −0.0044 (10) |
C9 | 0.0531 (15) | 0.0413 (14) | 0.0492 (12) | −0.0033 (11) | −0.0104 (10) | −0.0018 (10) |
C10 | 0.0412 (11) | 0.0388 (12) | 0.0301 (9) | −0.0009 (9) | −0.0006 (8) | −0.0038 (8) |
C11 | 0.095 (2) | 0.0536 (17) | 0.0604 (17) | −0.0116 (17) | −0.0407 (16) | 0.0130 (13) |
S1—C10 | 1.667 (2) | C1—C2 | 1.462 (3) |
Br1—C7 | 1.893 (2) | C3—C11 | 1.486 (3) |
O1—C2 | 1.214 (3) | C4—C9 | 1.377 (4) |
N1—C2 | 1.394 (3) | C4—C5 | 1.387 (3) |
N1—C10 | 1.401 (3) | C5—C6 | 1.378 (4) |
N1—N2 | 1.420 (3) | C5—H5A | 0.9300 |
N2—C3 | 1.289 (3) | C6—C7 | 1.375 (4) |
N3—C1 | 1.304 (3) | C6—H6A | 0.9300 |
N3—N4 | 1.308 (3) | C7—C8 | 1.389 (4) |
N4—C4 | 1.404 (3) | C8—C9 | 1.379 (4) |
N4—H1N4 | 0.82 (3) | C8—H8A | 0.9300 |
N5—C10 | 1.311 (3) | C9—H9A | 0.9300 |
N5—H1N5 | 0.81 (4) | C11—H11A | 0.9600 |
N5—H2N5 | 0.81 (4) | C11—H11B | 0.9600 |
C1—C3 | 1.435 (3) | C11—H11C | 0.9600 |
C2—N1—C10 | 130.42 (19) | C6—C5—H5A | 120.3 |
C2—N1—N2 | 111.85 (17) | C4—C5—H5A | 120.3 |
C10—N1—N2 | 117.67 (18) | C7—C6—C5 | 119.8 (2) |
C3—N2—N1 | 107.16 (19) | C7—C6—H6A | 120.1 |
C1—N3—N4 | 118.3 (2) | C5—C6—H6A | 120.1 |
N3—N4—C4 | 119.5 (2) | C6—C7—C8 | 121.3 (2) |
N3—N4—H1N4 | 131 (2) | C6—C7—Br1 | 118.24 (19) |
C4—N4—H1N4 | 110 (2) | C8—C7—Br1 | 120.5 (2) |
C10—N5—H1N5 | 117 (3) | C9—C8—C7 | 118.6 (3) |
C10—N5—H2N5 | 117 (2) | C9—C8—H8A | 120.7 |
H1N5—N5—H2N5 | 125 (4) | C7—C8—H8A | 120.7 |
N3—C1—C3 | 125.1 (2) | C4—C9—C8 | 120.4 (2) |
N3—C1—C2 | 128.6 (2) | C4—C9—H9A | 119.8 |
C3—C1—C2 | 106.37 (19) | C8—C9—H9A | 119.8 |
O1—C2—N1 | 130.2 (2) | N5—C10—N1 | 113.5 (2) |
O1—C2—C1 | 126.8 (2) | N5—C10—S1 | 124.77 (17) |
N1—C2—C1 | 103.00 (18) | N1—C10—S1 | 121.74 (17) |
N2—C3—C1 | 111.6 (2) | C3—C11—H11A | 109.5 |
N2—C3—C11 | 122.7 (2) | C3—C11—H11B | 109.5 |
C1—C3—C11 | 125.7 (2) | H11A—C11—H11B | 109.5 |
C9—C4—C5 | 120.5 (2) | C3—C11—H11C | 109.5 |
C9—C4—N4 | 119.0 (2) | H11A—C11—H11C | 109.5 |
C5—C4—N4 | 120.4 (2) | H11B—C11—H11C | 109.5 |
C6—C5—C4 | 119.3 (3) | ||
C2—N1—N2—C3 | −2.1 (3) | C2—C1—C3—C11 | −178.2 (3) |
C10—N1—N2—C3 | −179.5 (2) | N3—N4—C4—C9 | −176.6 (2) |
C1—N3—N4—C4 | −178.2 (2) | N3—N4—C4—C5 | 1.5 (4) |
N4—N3—C1—C3 | −178.7 (2) | C9—C4—C5—C6 | 0.8 (4) |
N4—N3—C1—C2 | 2.4 (4) | N4—C4—C5—C6 | −177.4 (3) |
C10—N1—C2—O1 | 0.6 (4) | C4—C5—C6—C7 | −0.8 (5) |
N2—N1—C2—O1 | −176.3 (2) | C5—C6—C7—C8 | 0.3 (5) |
C10—N1—C2—C1 | 179.5 (2) | C5—C6—C7—Br1 | 178.7 (2) |
N2—N1—C2—C1 | 2.6 (2) | C6—C7—C8—C9 | 0.3 (4) |
N3—C1—C2—O1 | −4.0 (4) | Br1—C7—C8—C9 | −178.1 (2) |
C3—C1—C2—O1 | 176.9 (2) | C5—C4—C9—C8 | −0.2 (4) |
N3—C1—C2—N1 | 177.0 (3) | N4—C4—C9—C8 | 178.0 (2) |
C3—C1—C2—N1 | −2.0 (3) | C7—C8—C9—C4 | −0.4 (4) |
N1—N2—C3—C1 | 0.7 (3) | C2—N1—C10—N5 | −167.1 (2) |
N1—N2—C3—C11 | 179.8 (3) | N2—N1—C10—N5 | 9.7 (3) |
N3—C1—C3—N2 | −178.2 (3) | C2—N1—C10—S1 | 13.9 (4) |
C2—C1—C3—N2 | 0.9 (3) | N2—N1—C10—S1 | −169.28 (17) |
N3—C1—C3—C11 | 2.6 (5) |
D—H···A | D—H | H···A | D···A | D—H···A |
N4—H1N4···O1 | 0.82 (4) | 2.27 (4) | 2.788 (3) | 121 (3) |
N5—H1N5···S1i | 0.80 (4) | 2.84 (4) | 3.522 (2) | 144 (3) |
N5—H2N5···O1ii | 0.82 (3) | 2.11 (4) | 2.925 (3) | 175 (4) |
Symmetry codes: (i) x, −y+1, z+1/2; (ii) −x+1/2, y−1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C11H10BrN5OS |
Mr | 340.21 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 296 |
a, b, c (Å) | 25.6080 (18), 11.6686 (8), 9.0823 (6) |
β (°) | 98.907 (2) |
V (Å3) | 2681.2 (3) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 3.22 |
Crystal size (mm) | 0.48 × 0.33 × 0.17 |
Data collection | |
Diffractometer | Bruker APEXII DUO CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.306, 0.609 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 15576, 3869, 2776 |
Rint | 0.034 |
(sin θ/λ)max (Å−1) | 0.703 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.040, 0.127, 1.03 |
No. of reflections | 3869 |
No. of parameters | 185 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.46, −0.75 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N4—H1N4···O1 | 0.82 (4) | 2.27 (4) | 2.788 (3) | 121 (3) |
N5—H1N5···S1i | 0.80 (4) | 2.84 (4) | 3.522 (2) | 144 (3) |
N5—H2N5···O1ii | 0.82 (3) | 2.11 (4) | 2.925 (3) | 175 (4) |
Symmetry codes: (i) x, −y+1, z+1/2; (ii) −x+1/2, y−1/2, −z+1/2. |
Footnotes
‡Thomson Reuters ResearcherID: A-3561-2009.
Acknowledgements
HKF and MH thank the Malaysian Government and Universiti Sains Malaysia for the Research University Grant No. 1001/PFIZIK/811160. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship.
References
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The pyrazole ring is a prominent structural moiety found in numerous pharmaceutically active compounds. This is mainly due to the easy preparation and the important pharmacological activity. Therefore, the synthesis and selective functionalization of pyrazoles have been the focus of active research area over the years (Isloor et al., 2009). Pyrazoles have been reported to possess antibacterial activity (Rai et al., 2008), and inhibitor activity against DNA gyrase and topoisomerase IV at their respective ATP-binding sites (Bradbury & Pucci, 2008). Moreover, pyrazole-containing compounds have received considerable attention owing to their diverse chemotherapeutic potentials including versatile anti-inflammatory and antimicrobial activities (Girisha et al., 2010). The synthetic route followed for obtaining the title compound involves the diazotization of substituted anilines to give the diazonium salts followed by coupling with ethyl acetoacetate in the presence of sodium acetate to give the corresponding oxobutanoate which on further reaction with thiosemicarbazide in acetic acid gave the required thioamides.
The asymmetric unit of the title compound (I) is shown in Fig. 1. The pyrazole (N1,N2/C1–C3) ring is approximately planar, with a maximum deviation of 0.014 (2) Å for atom N1. The dihedral angle between the benzene (C4–C9) ring and the pyrazole (N1,N2/C1–C3) ring is 5.49 (13)°. An intramolecular N4—H1N4···O1 hydrogen bond generates an S(6) ring motif (Bernstein et al., 1995). The bond lengths (Allen et al., 1987) and angles are within normal ranges.
In the crystal structure (Fig. 2) molecules are linked through intermolecular N5—H1N5···S1i and N5—H2N5···O1ii hydrogen bonds (Table 1) forming a two-dimensional network parallel to (1 0 0). A short Br···Br contact of 3.5114 (6) Å is also observed.